Hopefully, I'm about to make a fairly obvious point. For some reason, I just feel like making it extremely clear before going ahead with a new post thread I have in mind.
Common sense suggests most people in the Roman East were at least semi-fluent in greek. It's probably safe to assume places like Bethlehem and Nazareth heard less greek spoken than Jerusalem, which probably spoke less greek than Caesarea, but there's no question it was prudent for most folks in all places to know at least a few words in the "lingua franca" of their time. So... what about Jesus?
If Joseph and Mary chose Alexandria for their 2+ years in Egypt, Jesus definitely heard Jews speaking greek, probably from before he was able to talk. But did he speak it? Probably a better question is, how much did he speak it? Assuming the "red letters" of scripture are historically accurate renderings (verbatim quality being a whole separate issue), it would be as extreme to suppose they were all spoken in greek as that none of them were. More likely, if Jesus knew some greek, he probably used it only sometimes.
For instance, when large crowds followed Him from Syria and the Decapolis, someone could have translated as Jesus spoke, but he could have spoken some in greek also. When Jesus spoke at the Nazarene Synagogue? Probably Aramaic. When Jesus responded to Pilate? Probably Greek. Of course we can't say for sure, but my point is merely that the admittedly open question is not a singular one. There are separate considerations for any particular occasion.
Again, this should be an obvious point. I'm aware it's been made elsewhere. But now I feel more comfortable plowing forward into the post I really wanted to write... which will probably post here some time tomorrow:
Did Jesus Speak Greek at the fish fry in John 21?
Bill Heroman, Amateur Academic